Folding chair



Au'g- 9, 1960 E. F. HAMILTON 2,948,332

2 Sheets-Sheet 1 Amr.-

36' `n 5352 50 35 INVENroR.

34 F4 55 Z 15 5712/. fHHM/L rafv, fa

Aug. 9, 1960 E. F. HAMILTON FOLDING .CHAIR Filed sept. e, 1957 a l llllil 2 Sheets-Sheet 2 EL /FWnM/L ram, BY

nited States Patentfic-e 2,943,332l FOLDING CHAIR Earl F. Hamilton, Columbus, Ind., assignorto Hamilton Cosco, Inc., a corporation of Indiana Filed Sept. 6, 1957, Ser. No. '682,366

8 Claims. (Cl. 155-142) This invention relates to furniture, and more particularly to collapsible chairs in which the front legs and chair seat are foldable from an operative position into a collapsed position in which they are disposed substantially in the plane of .the .chair back.

The present invention relates primarily tothe type of chair just indicated and has for an object thereof to simplify and improve the assembly of such articles. Another object is to provide a chair which when its parts are disposed in operative position will otter but little indication of its collapsibility. A further object is to provide a collapsible chair whose retraction and extension may be readily and easily effected, and which can be releasably locked in either of said collapsed or extended positions. A further object is to provide a collapsible chair which lends itself to manufacture largely from sturdy and economical metal tubing and sheet metal.

ln carrying out my invention in its preferred form, I

Patented Aug. 9,- 1960 Fig. 2 is a side elevation showing the chair of Fig. 1 in fully collapsed storage position;

Fig. 2a is a View similar to Fig. 2 showing the chair in partially collapsed condition;

Fig. A3 is a lonigtudinal detail section showing the pivotal seat construction;

Fig. 4A is a rear elevation of the chair shown in Fig. 2;

Fig. 5 is a vertical section taken on the line 5--5 of Fig. 4; and

Fig. 6 is a View generally similar to Fig. 3 show-ing a moditication. f

The chair shown in the drawings comprises a back 10 and a seat 12 supported upon a pair of fro'nt legs 14 and a pair of rear legs 16. Conveniently, the rear legs 16 provide a pair of rear legs conveniently formed from metal tubing and rigidly secured to the chair back. A generally U-shaped frame is pivotally mounted to the lchair back with the legs of said` frame extending obliquely downward to form the front chair legs. The seat is pivoted to the rear legs near Vits rear edge and is connected to the front legs by links which are pivoted on a common axis to the seat at the sides thereof and extend, kwhen the chair is in operative position, vgenerally forwardly for pivotal `connection on a second common axis to the front legs. The front-supporting legs are interconnected by a seat-supporting rod, which may serve as the pivot interconnecting the front legs and the links. If desired, a detent device may be employed to hold the seat releasably in .contact with its supporting rod.

With this construction, chair collapse is readily eifected ,by` tilting the chair Lforwardly to llift the rear legs from -eiect, a toggle which can be forced through and beyond its position of greatest extension -with accompanying introduction of stresses into the chair-parts; and such stresses thereafter serve to maintain the chair collapsed. Toextend the chair, the front edge of the seat is forced forwardlyor the rear legs rearwardly to break or open the toggle, whereupon the seat and rear legs may readilyv be moved to their operative positions.

The accompanying drawings illustrate one embodiment of my invention. In such drawings:

Fig. 1 is a side elevation of a chairembodying my invention, the chair being shown in an extended operative position;

are identical in construction, each being formed from a length of metal tubing bent at its mid-portion to throw its lower end rearwardly. The upper end of each rear leg 16 is attened and bent to form a hook 18 having a generally semicircular curvature terminating in an upwardly extending lip 20. As shown in Fig. 5, the rearsupporting llegs 16 are mounted to the chair back 10 by inserting the lips 20 into slots 22 cut in the back frame 24 of a chair back 10 and then pivoting the legs downwardlyragainst the back frame 24 with the lips 20 bearing against the inner face of the frame 24. Completion of the desired rigid connection between the legs 16 and back 10 is conveniently effected by means of bolts 26 which extend through countersunk openings 28 disposed adjacent the top of said legs and through suitable openings cut in the chair back frame 24. Desirably, the rear legs 16 diverge downwardly from the back 10 to the iloor disposing their bottoms laterally outward to form a broad supporting base for the chair when it is in operative position.

The rear-supporting legs 16 are pivotally connected to the chair seat 12 by means of -a rod 3-2 having its in-bent ends 33 rotatably received in suitable coaxial openings in the outer faces of the legs and defining the pivotal axis of the 'chair seat .12. The center portion of the rod 32 is oifset laterally from the ends 33 `and rigidly connected to the seat 12. As shofwn, the seat embodies a seat-pan 34 having a depending peripheral lip 36 and forming the basic structural support for the chair seat 12; and the rod is clamped to the pan 34 by a pair of clips 38 secured to the lower :face of the seat pan 34 in a manner similar to the rear leg-chair back mounting. That is,

one end of each of the clips -38 comprises a tab 40 insertend comprises a tab 42 secured to the lower face of the pan 34 by means of a bolt 44.

The front legs 14 are conveniently the generally parallel stretches of a tubular U-shaped frame the intermediate or bight portion 46 of which is rotatably received between the chair back frame 24 and the rear leg hooks 18, therebyfpermitting the fro-nt legs 14 to swing vertically about the axis of the horizontal bight portion 46 during extension and retraction of the chair.

The front-supporting legs 14 are interconnected and cross-braced by a seat-supporting rod 48 having its ends received in suitable aligned openings along the inner faces of the legs 14. Connecting the front legs 14 to the chair seat 12 is a pair of toggle links 50 each of which is pivotally connected to the inner face of the seat-pan flange 36 on each lateral side of the seat by any suitable means, such as a bolt 52. The opposite end of each of the toggle links 50 is provided with an opening adapted to receive the transversely extending seat-supporting rod 48. Conveniently, the metal of the seat'pan 34 is offset upwardly at the sides thereof to form recesses 54 receiving the toggle links 50 when the chair is `in a collapsed storage position. l i l Y' Centered on the lower face of the seat pan 34, I havel vclip and seat pan. Upon extension ofthe chair into an operative position, the seat-supporting rod 48 engages the rearwardly open loop of the clip 58 and is yieldably retained therein for releasably locking the chair -in extended position.

Conveniently, both the front and rear legs f4 and i6 are bent rearwardly at their mid-portions sothat with the chair in extendedposition the front legs 14 intersect the plane of the seat 12 at its mid-point and disposeV the seat-supporting rod 4S ,forwardly of the center of the ground-engaging base Vformed by the extended fornt and rear legs. Thus, the seat 12 is supported both forwardly and rearwardly of the center Yof the base by the rods 48 and S2 respectively to equalize weight distribution and rgive the chair added stability. Further, by positioning the upper portion of the front legs well forward of the upper portions of the rear legs when the chair is in extended position the legs and seat form a bucket-type seat as shown in Fig. l.

Collapse of the chair from extended condition is most easily effected by tilting it forwardly to lift the rear legs 16 from the floor and by then applying an upward effortto the front of the seat to release the detent clip 58 from the rod 4S. applied to the front of the seat causes the links 50 to swing over `center and then downwardly in a counterclockwise direction about the rod 4S with the rear legs 16 swinging forwardly toward the front legs.

I have referred above to a toggle-like action which serves to hold the chair in fully collapsed condition. To facilitate explanation of that action, I have applied the reference letter A to the axis of pivotal connection between the front and rear legs, the letter B to the axis of pivotal connection between the front legs and the links 50, and the letter C to the axis of pivotal connection between the seat and the rear legs.

The chair is so designed that as the axis C, in collapse of the chair, approaches the common plane of axes A and B the peripheral lip 36 of the seat re-engages the rod 48. When this condition (illustrated in Fig. 2n) occurs, the links 59 can no longer swing relative to the seat, and the links and seat form in elfect a unitary element cooperating with the upper portions of the rear legs ,to form a toggle not quite completely extended. The chair-parts, and particularly the rods 32 and 48, however, are sufliciently resilient to permit further collapse of the `chair. In this further collapse, the axis C passes through the plane of the axes A and B, and thereafter the resilience of the stressed parts urges the rear legs forwardly. Forward swinging of the rear legs under such urging is limited by their engagement with the seat on the rod 48, the center portion of which may be offset forwardly to avoid premature interference with collapse of the rear legs.

The chair is firmly held in the collapsed position by the resilience of the parts which were stressed in the operation of collapsing the chair from the condition shown in Fig. 2a to that shown in Fig. 2. To extend the chair from completely collapsed condition, the lower edge of the seat is moved forwardly, or the rear legs rearwardly, to force the axis C through the plane of axes A and B, whereupon the seat may easily be swung into horizontal position. As a nal operation in extension of the chair, the seat is forced downwardly to engage the detent 58 With the rod 48.

In Fig. 6 I have shown a different form of means for releasably holding the chair in extended position. In that structure, `the spring detent 58 is eliminated and replaced by a latch 6-2 pivoted to the seat-lip 36 at one side of the seat, as by means of a rivet 64. Below the Further upward and forward effort' rivet 64, the latch is provided with a rearwardly opening notch adapted to receive the rod 48. The latch extends forwardly of the rivet 64 to provide a linger piece 66 the weight of which serves, when the seat 14 is raised, to bias the latch for counterclockwise swinging about the rivet 64. Such swinging of the latch is limited by engagement of its rear end with the lower surface of the seat pan 34, whereby, as the seat is lowered to horizontal position, the rod 48 will be engaged by a cam-like nose 68 on the `latch and the latch swung into the dottedline position shown in Fig. 6. When the seat reaches its linal horizontal position, the notch of the llatch will have come opposite the rod 48, and the latch will swing under the iniiuence of gravity to cause the notch to embrace the rod. The rivet 64 is so located and the notch so shaped that after the latch is engaged reaction of the rod 48 on the lower notch-wall will not cause the latch to lswing in the releasing direction. When it is desired to collapse the chair, the ynger piece 66 can be raised to the dotted-line position, thus freeing the notch from engagement with the rod 48 and permitting the front edge of the seat to be raised.

I claim as my invention:

1. A collapsible chair having a back and seat, comprising rear legs mounted to said back and engageable with the floor or other supporting surface, said rear legs being sceured to the rear face of said back and terminating at their upper ends in hook-like portions facing the back and cooperating therewith to denne a bearing, pivotal means interconnecting said legs and the chair seat, a front-supporting frame having a tranverse section pivotally received in said bearing and interconnecting a pair of front legs vertically swinging between a retracted position generally coplanar with said rear legs and an operative position in which the front legs are disposed well forwardly of the rear legs, and a seat-supportingrod interconnecting said front legs and vadapted to support the seat in operative position.

2. A collapsible chair having a back and a downwardly collapsible seat, comprising rear legs mounted to said back and engageable with the floor or other supporting surface, means' pivotally interconnecting the chair seat to said rear legs on a iixed pivotal axis, a U-shaped frontsupporting member comprising a transverse section pivotally supported across the chair back and a pair of generally parallel front legs movable about said pivotal support between a retracted position generally Vcoplanar with the rear legs' and an operative position in .which the lower stretchesof said legs are disposed well forwardly of the rear legs, said front legs intersecting the plane of said seat at Vits mid-portion in operative position, a seatsupporting rod interconnecting said front legs and adapted to support the seat in an operative position, link means extending between said rod and a pivotal axis on the seat and forming a toggle linkage fixing the relative positions of said front and rear legs, said seat upon chair collapse being swingable upwardly about said-first means to carry the rear ends of said link means upwardly, said upward movement breaking the toggle linkage and allowing the front legs to swing rearwardly through said pivot axis and the seat to swing downwardly into its collapsed position.

3. A collapsible chair having a back and a downwardly collapsible seat, comprising rear legs mounted to said back and engageable with the oor or other supporting surface, means pivotally interconnecting the chair seat to said rear legs on a fixed pivotal axis, a U-shaped frontsupporting member comprising a transverse section pivotally supported across the chair back and a pair of generally parallel front legs movable about said pivotal support between `a retracted position generally copl'anar with the rear legs and an operative position in which the `lower Vstretches of said legs are disposed well forwardly of the rear legs, said front legs intersecting the plane of said fantasias seat at its mid-portion in operative position, a seatsupporting rod interconnecting said front legs and adapted to support the seat in operative position, and a pair of links each having its opposite ends Ypivotally connected respectively to said seat-Supporting rod and the seat for releasably locking said seat in collapsed and extended po sitions and forming toggle linkages iixing the relative positions of the front andvrear legs, said links having a length shorter than the distance between the interconnections of the seat to the rear legs and said pair of links, said seat upon chair collapse being swingable upwardly about said means to carry the rear ends of said links upwardly, said upward movement breaking the toggle linkage and allowing the front legs to swing rearwardly and the seat to swing downwardly into its collapsed position in which it is generally coplanar with the lower stretches of the front and rear legs, said seat having on its lower surface laterally disposed recesses for nesting said toggle links when the seat is releasably locked in collapsed position.

4. A collapsible chair as set forth in claim 3 including a metal seat-pan forming 'a bottom of said seat, said recesses -being downwardly open grooves pressed into said seat-pan.

5. A collapsible chair, comprising a seat, front legs and rear legs pivotally interconnected on a horizontal axis above said seat and swingable relatively about such axis between a collapsed condition in which they are approximately coplanar and an extended condition in which they diverge downwardly, means pivotally connecting said rear legs to said seat adjacent the rear edge thereof, a pair of links connecting said seat to said front legs, means carried by said front legs for supporting the seat in generally horizontal position when the front and rear legs are in extended condition, said links when the chair is extended-extending generally rearwardly from a first common axis of pivotal connection to the front legs to a second common 'axis of pivot-al connection to the seat and being swingable upwardly, forwardly, and then downwardly as the front and rear legs move toward each other in collapse of the chair to bring the seat with the legs toward a generally coplanar relationship, and means operative as the legs near collapsed condition for limiting swinging movement of the links relative to the seat to confine further movement of the seat to rotation about said first common axis and cause the seat, in cooperation with the upper portions of the rear legs, to form in eiect an incompletely extended toggle, parts of the chair being elastically yieldable to permit such toggle to be forced through completely extended condition, the stresses introduced into such elastically yieldable parts serving to hold the legs and seat in substantially coplanar relationship.

6. A chair as described in claim 5 with the addition that said seat-supporting means comprises a rod extending between the front legs and through which said links are connected to the front legs.

7. A chair as described in claim 6 with the addition that said means for limiting Iswinging movement of the links comprises a portion of said seat engageable with said rod.

8. A collapsible chair as set forth in claim 4 with the addition of a latch member pivoted on said seat pan and releasably engageable with said seat-supporting rod.

References Cited in the le of this patent UNITED STATES PATENTS D. 175,994 Wagner Nov. 1, 1955 119,754 Gardner Oct. 10, 1871 1,638,879 Rastetter Aug. 16, 1927 2,238,817 Morgan et al. Apr. 15, 1941 2,666,478 Shwayder lan. 19, 1954 2,729,275l Morgan et al. Jan. 3, 1956 2,753,922 Griml'aud July 10, 1956 FOREIGN PATENTS 226,891 Switzerland Aug. 2, 1943 

